public class zheng extends GeometricObject {
    public double getLen() {
        return len;
    }

    public void setLen(double len) {
        this.len = len;
    }

    @Override
    public double getArea() {
        return len*len;
    }

    @Override
    public double getPerimeter() {
        return 4*len;
    }

    public double len;
    private zheng(){

    }
    public zheng(double len) {
        this.len = len;
    }

    public zheng(String color, boolean filled, double len) {
        super(color, filled);
        this.len = len;
    }
    
}
